JP2022064296A - Laser processing device - Google Patents

Abstract

To provide a laser processing device capable of easily adjusting the power of a laser beam with which a wafer is irradiated.SOLUTION: A laser processing device 500 includes holding means 502 that holds a wafer 4, laser beam irradiating means 504 that irradiates a boundary portion 22 between a device region 18 of the wafer 4 and an outer peripheral surplus region 20 held by the holding means 502 with a laser beam LB, and moving means 506 that relatively moves the holding means 502 and the laser beam irradiating means 504. The laser beam irradiating means 504 includes an oscillator 510 that oscillates the laser beam LB, a condenser 512 that collects the laser beam LB oscillated by the oscillator 510, a beam splitter 516 that is arranged between the condenser 512 and the oscillator 510 and splits the plasma light P emitted from the region processed by the irradiation of the laser beam LB and leads to a branch path 514, and plasma light detection means 518 that is arranged in the branch path 514 and detects the plasma light P.SELECTED DRAWING: Figure 13

Description

The present invention relates to a laser processing apparatus that irradiates a wafer having a device region formed on a surface in which a plurality of devices are partitioned by a planned division line and an outer peripheral surplus region surrounding the device region with a laser beam to perform processing.

The back surface of the wafer in which the device area in which a plurality of devices such as ICs and LSIs are divided by the planned division line and the outer peripheral surplus area surrounding the device area are formed on the front surface is formed to a desired thickness by grinding the back surface. Later, it is divided into individual device chips by a dicing device and a laser processing device, and each divided device chip is used for electric devices such as mobile phones and personal computers.

Since thinning the wafer makes it difficult to transport and perform additional processing, the applicant has applied a technique for grinding the back surface corresponding to the device region to form a ring-shaped reinforcing portion on the back surface corresponding to the outer peripheral surplus region. (See, for example, Patent Document 1).

When the wafer is divided into individual device chips, the ring-shaped reinforcing portion becomes an obstacle, so the boundary portion between the device region and the outer peripheral surplus region is irradiated with a laser beam to remove the ring-shaped reinforcing portion. ..

Japanese Unexamined Patent Publication No. 2015-147231

However, since the front surface or the back surface of the wafer may be additionally processed to coat a metal film or the like, the laser beam irradiating the wafer depends on the material of the substrate of the wafer or the material of the film coated on the wafer. There is a problem that the power must be adjusted appropriately and it cannot withstand the trouble.

An object of the present invention made in view of the above facts is to provide a laser processing apparatus capable of easily adjusting the power of a laser beam irradiating a wafer.

According to the present invention, the following laser processing apparatus that solves the above problems is provided. That is, it is a laser processing apparatus that irradiates a wafer having a device region formed on the surface of a plurality of devices divided by a planned division line and an outer peripheral surplus region surrounding the device region with a laser beam to perform processing. , The holding means for holding the waha, the laser beam irradiating means for irradiating the boundary between the device region and the outer peripheral surplus area of the waha held by the holding means, and the holding means and the laser beam irradiating means relative to each other. The laser beam irradiating means includes an oscillator that oscillates a laser beam, a condenser that condenses the laser beam oscillated by the oscillator, and plasma emitted from a region processed by the irradiation of the laser beam. A laser processing apparatus including a plasma light detecting means for detecting light is provided.

Further provided with a beam splitter which is arranged between the condenser and the oscillator and which splits the plasma light emitted from the region processed by the irradiation of the laser beam and guides it to the branch path, the plasma light detection means is the branch. It is desirable to be placed on the road. Preferably, the front surface or the back surface of the wafer is coated with a metal film, and a power setting means for selecting the type of material and setting the power of the laser beam is provided. If the type of material specified based on the plasma light detected by the plasma light detecting means and the type of material selected by the power setting means are different, it is preferable to issue an error. A recess is formed on the back surface corresponding to the device region of the wafer, a ring-shaped reinforcing portion is formed convexly on the back surface corresponding to the outer peripheral surplus region of the wafer, and the laser beam is applied to the base of the ring-shaped reinforcing portion. It is convenient to be irradiated. It is desirable to stop the irradiation of the laser beam when the plasma light detecting means stops detecting the plasma light.

In the laser processing apparatus of the present invention, a wafer having a device region formed on the surface of a plurality of devices partitioned by a planned division line and an outer peripheral surplus region surrounding the device region is irradiated with a laser beam to perform processing. A laser processing device, a holding means for holding a waha, a laser beam irradiating means for irradiating a boundary portion between a device region and an outer peripheral surplus area of the waha held by the holding means, and the holding means and the laser beam. The laser beam irradiating means is provided with a moving means for relatively moving the irradiating means, and the laser beam irradiating means is processed by irradiating the laser beam with an oscillator that oscillates the laser beam, a condenser that collects the laser beam oscillated by the oscillator, and the laser beam. Since it includes a plasma light detecting means for detecting the plasma light emitted from the region, the power of the laser beam irradiating the wafer can be easily obtained based on the detection result of the plasma light emitted from the region processed by the irradiation of the laser beam. Can be adjusted.

FIG. 3 is a perspective view of a processing unit including a laser processing apparatus configured according to the present invention. FIG. 3 is a perspective view of a wafer processed by the processing unit shown in FIG. 1. FIG. 3 is a perspective view of a wafer cassette table or the like shown in FIG. The perspective view of the hand shown in FIG. The perspective view of the frame accommodating means and the like shown in FIG. (A) A perspective view of a tape sticking means or the like when the frame table shown in FIG. 1 is located in the lowered position, and (b) tape sticking in a state where the frame table shown in FIG. 1 is located in the raised position. Perspective view of means and the like. An exploded perspective view of the tape crimping means shown in FIG. 1. The cross-sectional view which shows the state which starts pressing a tape by a pressing roller in a tape crimping process. The cross-sectional view which shows the state which the pressing of the tape by the pressing roller is completed in the tape crimping process. FIG. 3 is a perspective view of the reinforcing portion removing means shown in FIG. (A) Cross-sectional view of the frame support portion when the strong permanent magnet of the temporary placement table shown in FIG. 1 is located in the ascending position, and (b) the strong permanent magnet of the temporary placing table shown in FIG. 1 is located in the descending position. Cross-sectional view of the frame support part when it is. (A) A perspective view of the holding means of the laser processing apparatus shown in FIG. 1, and (b) a perspective view of the first elevating table shown in (a) as viewed from below. The block diagram which shows the structure of the laser beam irradiation means. (A) A graph showing an example of a signal input to a control means, (b) A table showing the relationship between the wavelength of plasma light, the material of a region subjected to laser processing, and the power of a laser beam. The schematic diagram which shows the state which irradiates the base of a wafer with a laser beam in the process of removing a reinforcing part. FIG. 3 is a perspective view of a separated portion of the reinforcing portion removing means shown in FIG. The schematic diagram which shows the state which the reinforcement part is separated from the wafer in the reinforcement part removal process. FIG. 3 is a perspective view of a discarded portion of the reinforcing portion removing means shown in FIG. FIG. 3 is a perspective view of a reversing mechanism of the ringless unit carrying-out means shown in FIG. FIG. 3 is a perspective view of a ringless unit support portion and a push-in portion of the ringless unit carrying-out means shown in FIG. The perspective view which shows the state which carries out the unit accommodating process without a ring.

Hereinafter, preferred embodiments of a laser processing apparatus configured according to the present invention will be described with reference to the drawings, taking as an example a processing unit including the laser processing apparatus of the present invention.

Explaining with reference to FIG. 1, the processing unit whose whole is indicated by reference numeral 2 is a wafer cassette table 8 on which a wafer cassette 6 accommodating a plurality of wafers is mounted and a wafer mounted on the wafer cassette table 8. The wafer carrying-out means 10 for carrying out the wafer from the cassette 6 and the wafer table 12 for supporting the surface side of the wafer carried out by the wafer carrying-out means 10 are provided.

FIG. 2 shows a wafer 4 processed by the processing unit 2. The surface 4a of the wafer 4 is formed with a device region 18 in which a plurality of devices 14 such as ICs and LSIs are partitioned by a grid-like division schedule line 16 and an outer peripheral surplus region 20 surrounding the device region 18. In FIG. 2, the boundary portion 22 between the device region 18 and the outer peripheral surplus region 20 is shown by a two-dot chain line for convenience, but the line indicating the boundary portion 22 does not actually exist. A circular recess 23 is formed on the back surface 4b corresponding to the device region 18 of the wafer 4, and a ring-shaped reinforcing portion 24 is formed convexly on the back surface 4b corresponding to the outer peripheral surplus region 20 of the wafer 4. The thickness of the outer peripheral surplus region 20 is larger than the thickness of the device region 18. Further, a notch 26 indicating the crystal orientation is formed on the peripheral edge of the wafer 4. The front surface 4a or the back surface 4b of the wafer 4 may be coated with a metal film such as aluminum or copper.

As shown in FIG. 3, a plurality of wafers 4 are housed in the cassette 6 with the surface 4a facing upward at intervals in the vertical direction. The wafer cassette table 8 of the illustrated embodiment has a top plate 28 on which the cassette 6 is placed and a support plate 30 for supporting the top plate 28. The top plate 28 can be raised and lowered, and a raising and lowering means for raising and lowering the top plate 28 and positioning it at an arbitrary height may be provided.

Continuing the description with reference to FIG. 3, the wafer carrying-out means 10 moves the Y-axis movable member 32, which is movable in the Y-axis direction indicated by the arrow Y in FIG. 3, and the Y-axis movable member 32 in the Y-axis direction. It is provided with a Y-axis feed means 34. The Y-axis feeding means 34 has a ball screw 36 connected to the lower end of the Y-axis movable member 32 and extending in the Y-axis direction, and a motor 38 for rotating the ball screw 36. The Y-axis feed means 34 converts the rotational motion of the motor 38 into a linear motion by the ball screw 36 and transmits it to the Y-axis movable member 32, and the Y-axis movable member 32 is transmitted along the pair of guide rails 40 extending in the Y-axis direction. Is moved in the Y-axis direction. The X-axis direction indicated by the arrow X in FIG. 3 is a direction orthogonal to the Y-axis direction, and the Z-axis direction indicated by the arrow Z in FIG. 3 is a vertical direction orthogonal to the X-axis direction and the Y-axis direction. The XY plane defined by the X-axis direction and the Y-axis direction is substantially horizontal.

As shown in FIG. 3, the wafer unloading means 10 of the illustrated embodiment supports the transfer arm 42 and the back surface 4b of the wafer 4 disposed at the tip of the transfer arm 42 and housed in the wafer cassette 6, and the front and back surfaces of the wafer 4 are supported. It is provided with a hand 44 for reversing. The transfer arm 42 is provided on the upper surface of the Y-axis movable member 32, and is driven by an appropriate drive source (not shown) such as an air drive source or an electric drive source. This drive source drives the transport arm 42 to position the hand 44 at an arbitrary position in each of the X-axis direction, the Y-axis direction, and the Z-axis direction, and invert the hand 44 upside down.

Explaining with reference to FIG. 4, the hand 44 is preferably a Bernoulli pad in which a negative pressure is generated by the ejection of air to support the wafer 4 in a non-contact manner. The hand 44 of the illustrated embodiment has a C shape as a whole, and a plurality of air outlets 46 connected to a compressed air supply source (not shown) are formed on one side of the hand 44. A plurality of guide pins 48 are attached to the outer peripheral edge of the hand 44 at intervals in the circumferential direction. Each guide pin 48 is configured to be movable in the radial direction of the hand 44.

As shown in FIGS. 3 and 4, the wafer carrying-out means 10 positions the hand 44 on the back surface 4b side (lower side) of the wafer 4 in the wafer cassette 6 placed on the wafer cassette table 8, and then the hand 44. Compressed air is ejected from the air ejection port 46 to generate a negative pressure on one side of the hand 44 by the Bernoulli effect, and the wafer 4 is suction-supported from the back surface 4b side by the hand 44 in a non-contact manner. The horizontal movement of the wafer 4 suction-supported by the hand 44 is regulated by each guide pin 48. Then, the wafer carrying-out means 10 moves the Y-axis movable member 32 and the transport arm 42 to carry out the wafer 4 sucked and supported by the hand 44 from the wafer cassette 6.

As shown in FIG. 4, the wafer carrying-out means 10 of the illustrated embodiment includes a notch detecting means 50 for detecting the position of the notch 26 of the wafer 4. The notch detecting means 50 is, for example, a drive source (not shown) that rotates at least one of a light emitting element 52 and a light receiving element 54 arranged at intervals in the vertical direction and a guide pin 48 of the hand 44. ) May be included.

The light emitting element 52 and the light receiving element 54 may be attached to the Y-axis movable member 32 or the transport path via an appropriate bracket (not shown). Further, when the guide pin 48 is rotated by the drive source, the wafer 4 sucked and supported by the hand 44 is rotated due to the rotation of the guide pin 48. In order to reliably transmit rotation from the guide pin 48 to the wafer 4, it is preferable that the outer peripheral surface of the guide pin 48 rotated by the drive source is formed of an appropriate synthetic rubber.

The notch detecting means 50 is a drive source via a guide pin 48 in a state where the wafer 4 is suction-supported by the hand 44 and the outer periphery of the wafer 4 is positioned between the light emitting element 52 and the light receiving element 54. By rotating the wafer 4, the position of the notch 26 can be detected. This makes it possible to adjust the orientation of the wafer 4 to any orientation.

As shown in FIG. 3, the wafer table 12 is arranged adjacent to the wafer carrying-out means 10. The wafer table 12 of the illustrated embodiment is disposed on the outer periphery of the annular support portion 56 and the annular support portion 56 that supports the outer peripheral surplus region 20 of the wafer 4 and makes the portion inside the outer peripheral surplus region 20 non-contact. A frame support portion 58 that supports the frame 64 (see FIG. 5) described later is provided. A plurality of suction holes 60 arranged at intervals in the circumferential direction are formed on the upper surface of the annular support portion 56, and each suction hole 60 is connected to a suction means (not shown). The inner portion in the radial direction of the annular support portion 56 of the wafer table 12 is a circular recess 62 that is recessed downward.

When the wafer 4 is placed on the wafer table 12 with the hand 44 inverted 180 ° and the front and back of the wafer 4 inverted and the surface 4a of the wafer 4 faces downward, the outer peripheral excess region 20 of the wafer 4 is annularly supported. Supported by the portion 56, the device region 18 of the wafer 4 is located in the recess 62. Therefore, even if the wafer 4 is placed on the wafer table 12 with the surface 4a on which the device 14 is formed facing downward, the device 14 and the wafer table 12 do not come into contact with each other, so that the device 14 is damaged. Be prevented. Further, the wafer table 12 supports the outer peripheral surplus area 20 by the annular support portion 56, and then operates the suction means to generate suction force in each suction hole 60 to suck and hold the outer peripheral surplus area 20. Prevents misalignment of.

Explaining with reference to FIG. 5, the processing unit 2 further includes a frame accommodating means 66 accommodating a plurality of ring-shaped frames 64 having an opening 64a for accommodating the wafer 4, and frame accommodating means 66 to the frame 64. The frame carrying-out means 68 and the frame table 70 supporting the frame 64 carried out by the frame carrying-out means 68 are provided.

As shown in FIG. 5, the frame accommodating means 66 of the illustrated embodiment has a housing 72, an elevating plate 74 movably arranged in the housing 72, and an elevating means for raising and lowering the elevating plate 74 (not shown). ) And. In FIG. 5, a Z-axis guide member 78 extending in the Z-axis direction is arranged on the side surface of the housing 72 on the back side in the X-axis direction. The elevating plate 74 is supported by the Z-axis guide member 78 so as to be able to move up and down, and the elevating means for raising and lowering the elevating plate 74 is arranged inside the Z-axis guide member 78. The elevating means may have, for example, a configuration having a ball screw connected to the elevating plate 74 and extending in the Z-axis direction, and a motor for rotating the ball screw. In FIG. 5, a door 76 to which a handle 76a is attached is provided on the front side surface of the housing 72 in the X-axis direction. In the frame accommodating means 66, the door 76 is opened by grasping the handle 76a. The frame 64 can be accommodated inside the housing 72. Further, an opening 80 is provided at the upper end of the housing 72.

As shown in FIG. 5, the frame 64 made of a magnetic material is laminated and accommodated on the upper surface of the elevating plate 74 inside the housing 72. Of the plurality of stacked frames 64, the uppermost frame 64 is carried out from the opening 80 of the housing 72 by the frame carrying out means 68. Further, when the frame 64 is carried out from the opening 80, the frame accommodating means 66 appropriately raises the elevating plate 74 by the elevating means, and positions the uppermost frame 64 at a position where the frame 64 can be carried out by the frame carrying out means 68.

Continuing the description with reference to FIG. 5, the frame carrying-out means 68 has an X-axis guide member 82 fixed to an appropriate bracket (not shown) and extending in the X-axis direction, and an X-axis guide member 82 movably movable in the X-axis direction. An X-axis movable member 84 supported by the axis guide member 82, an X-axis feed means (not shown) for moving the X-axis movable member 84 in the X-axis direction, and an X-axis movable so as to be movable in the Z-axis direction. A Z-axis movable member 86 supported by the member 84 and a Z-axis feeding means (not shown) for moving the Z-axis movable member 86 in the Z-axis direction are included. The X-axis feeding means of the frame carrying-out means 68 may have a configuration including a ball screw connected to the X-axis movable member 84 and extending in the X-axis direction, and a motor for rotating the ball screw, and the Z-axis feeding means is the Z-axis. A configuration may include a ball screw connected to the movable member 86 and extending in the Z-axis direction, and a motor for rotating the ball screw.

The Z-axis movable member 86 of the frame carrying-out means 68 has a holding portion 88 for holding the frame 64. The holding portion 88 of the illustrated embodiment has a rectangular substrate 90 and a plurality of suction pads 92 provided on the lower surface of the substrate 90, and each suction pad 92 is used as a suction means (not shown). It is connected.

The frame carrying-out means 68 sucks and holds the uppermost frame 64 housed in the frame accommodating means 66 by the suction pad 92 of the holding portion 88, and then moves the X-axis movable member 84 and the Z-axis movable member 86. , The uppermost frame 64 sucked and held is carried out from the frame accommodating means 66.

As shown in FIG. 5, the frame table 70 is supported by the Z-axis guide member 94 so as to be able to move up and down between the lowering position shown by the solid line and the rising position shown by the alternate long and short dash line. The Z-axis guide member 94 is provided with an appropriate drive source (for example, an air drive source or an electric drive source) for raising and lowering the frame table 70 between the descending position and the ascending position. In the frame table 70, the frame 64 carried out by the frame carrying-out means 68 is received at the lowered position.

As shown in FIGS. 1 and 5, the processing unit 2 is arranged above the frame table 70, and the tape attaching means 98 (see FIG. 1) for attaching the tape 96 to the frame 64 and the tape 96 are attached. The frame 64 (hereinafter sometimes referred to as "frame with tape 64'") is conveyed to the wafer table 12 and the opening 64a of the frame 64 is positioned on the back surface 4b of the wafer 4 supported by the wafer table 12 and attached with tape. The frame transporting means 100 with tape for placing the frame 64'on the wafer table 12 (see FIG. 5) and the tape crimping means 102 for crimping the tape 96 of the frame 64'with tape to the back surface 4b of the wafer 4 (see FIG. 1). .) And including.

Explaining with reference to FIG. 6, the tape attaching means 98 of the illustrated embodiment winds the roll tape support portion 104 that supports the roll tape 96R on which the tape 96 before use is wound, and the used tape 96. The tape winding portion 106 to be taken, the tape pulling out portion 108 for pulling out the tape 96 from the roll tape 96R, the crimping portion 110 for crimping the pulled out tape 96 to the frame 64, and the tape 96 protruding from the outer periphery of the frame 64 are framed 64. It is provided with a cutting portion 112 for cutting along the line.

As shown in FIG. 6, the roll tape support portion 104 includes a support roller 114 rotatably supported by an appropriate bracket (not shown) about an axis extending in the X-axis direction. The support roller 114 is supported by a roll tape 96R in which a release paper 116 for protecting the adhesive surface of the tape 96 is attached to the adhesive surface of the tape 96 and wound in a cylindrical shape.

The tape take-up portion 106 includes a take-up roller 118 rotatably supported by an appropriate bracket (not shown) about an axis extending in the X-axis direction, and a motor (shown) for rotating the take-up roller 118. Not included.) As shown in FIG. 6, the tape take-up portion 106 winds up the used tape 96 having a circular opening 120 that hits the portion attached to the frame 64 by rotating the take-up roller 118 by a motor. ..

Continuing the description with reference to FIG. 6, the tape pull-out portion 108 is a pull-out roller 122 arranged below the support roller 114 of the roll tape support portion 104, and a motor for rotating the pull-out roller 122 (not shown). ) And a driven roller 124 that rotates with the rotation of the drawer roller 122. The tape pull-out portion 108 pulls out the tape 96 sandwiched between the pull-out roller 122 and the driven roller 124 from the roll tape 96R by rotating the driven roller 124 together with the pull-out roller 122 by a motor.

The release paper 116 is peeled from the tape 96 that has passed between the pull-out roller 122 and the driven roller 124, and the peeled paper 116 is taken up by the release paper winding unit 126. The release paper winding unit 126 of the illustrated embodiment has a release paper winding roller 128 arranged above the driven roller 124 and a motor (not shown) for rotating the release paper winding roller 128. Further, the tape 96 from which the release paper 116 has been peeled off is guided to the take-up roller 118 via a guide roller 130 arranged at a distance in the Y-axis direction from the drawer roller 122.

The crimping portion 110 includes a pressing roller 132 movably arranged in the Y-axis direction and a Y-axis feeding means (not shown) for moving the pressing roller 132 in the Y-axis direction. The Y-axis feed means of the crimping portion 110 may be composed of an appropriate drive source (for example, an air drive source or an electric drive source).

As shown in FIG. 6, the cutting portion 112 is supported by a Z-axis guide member 134 fixed to an appropriate bracket (not shown) and extending in the Z-axis direction and a Z-axis guide member 134 movably movable in the Z-axis direction. The Z-axis movable member 136 is included, and a Z-axis feeding means (not shown) for moving the Z-axis movable member 136 in the Z-axis direction is included. The Z-axis feed means of the cutting portion 112 may have a configuration including a ball screw connected to the Z-axis movable member 136 and extending in the Z-axis direction, and a motor for rotating the ball screw.

Further, the cutting portion 112 includes a motor 138 fixed to the lower surface of the tip of the Z-axis movable member 136, and an arm piece 140 rotated by the motor 138 about an axis extending in the Z-axis direction. The first and second hanging pieces 142a and 142b are attached to the lower surface of the arm piece 140 at intervals from each other. The first hanging piece 142a supports a circular cutter 144 rotatably around an axis orthogonal to the Z-axis direction, and the second hanging piece 142b rotates about an axis orthogonal to the Z-axis direction. The holding roller 146 is freely supported.

Before the frame table 70, which has received the frame 64 from the frame unloading means 68, is positioned from the descending position (position shown in FIG. 6A) to the ascending position (position shown in FIG. 6B), the tape attaching means 98 Pulls out the unused tape 96 by the pull-out roller 122 and the driven roller 124. Then, the frame table 70 is positioned in the ascending position so that the tape 96 can be pressed against the frame 64 by the pressing roller 132 of the crimping portion 110, and the frame 64 is brought into contact with the pressing roller 132 via the tape 96. Then, the pressing roller 132 is rolled in the Y-axis direction while pressing the adhesive surface of the tape 96 against the frame 64 with the pressing roller 132. As a result, the tape 96 drawn from the roll tape 96R by the tape pulling out portion 108 can be crimped to the frame 64.

After crimping the tape 96 to the frame 64, the tape attaching means 98 lowers the Z-axis movable member 136 of the cutting portion 112 by the Z-axis feeding means, presses the cutter 144 against the tape 96 on the frame 64, and presses the roller. Press the frame 64 from above the tape 96 with 146. Next, the arm piece 140 is rotated by the motor 138, and the cutter 144 and the pressing roller 146 are moved along the frame 64 in a circular motion. As a result, the tape 96 protruding from the outer periphery of the frame 64 can be cut along the frame 64. Further, since the frame 64 is pressed from above the tape 96 by the pressing roller 146, the misalignment of the frame 64 and the tape 96 is prevented when the tape 96 is cut. Then, after the frame table 70 is lowered, the used tape 96 having the circular opening 120 corresponding to the portion attached to the frame 64 is wound by the tape winding portion 106.

As shown in FIG. 5, the frame transfer stage 100 with tape has a Y-axis guide member 148 fixed to an appropriate bracket (not shown) and extending in the Y-axis direction, and a Y-axis guide member movably movable in the Y-axis direction. The Y-axis movable member 150 supported by 148, the Y-axis feed means (not shown) for moving the Y-axis movable member 150 in the Y-axis direction, and the Y-axis movable member 150 movably movable in the Z-axis direction. It includes a supported Z-axis movable member 152 and a Z-axis feeding means (not shown) for moving the Z-axis movable member 152 in the Z-axis direction. The Y-axis feeding means of the frame transport stage 100 with tape may have a configuration including a ball screw connected to the Y-axis movable member 150 and extending in the Y-axis direction, and a motor for rotating the ball screw. A configuration may include a ball screw connected to the Z-axis movable member 152 and extending in the Z-axis direction, and a motor for rotating the ball screw.

The Z-axis movable member 152 of the frame transporting means 100 with tape has a holding portion 154 for holding the frame 64'with tape. The holding portion 154 of the illustrated embodiment has a rectangular substrate 156 and a plurality of suction pads 158 provided on the lower surface of the substrate 156, and each suction pad 158 is used as a suction means (not shown). It is connected.

The frame transporting means 100 with tape sucks and holds the upper surface of the frame 64'with tape supported by the frame table 70 with the adhesive surface of the tape 96 facing down by each suction pad 158 of the holding portion 154, and Y By moving the axial movable member 150 and the Z-axis movable member 152, the frame 64'with tape sucked and held by the holding portion 154 is conveyed from the frame table 70 to the wafer table 12, and the wafer 4 supported by the wafer table 12 is conveyed. The opening 64a of the frame 64 is positioned on the back surface 4b, and the frame 64'with tape is placed on the wafer table 12.

The tape crimping means 102 will be described with reference to FIGS. 7 to 9. As shown in FIG. 7, the tape crimping means 102 raises and lowers the upper chamber 160 arranged above the wafer table 12, the lower chamber 162 accommodating the wafer table 12, and the upper chamber 160 to bring them into contact with the lower chamber 162. An elevating mechanism 164 that creates a closed state and an open state separated from the lower chamber 162, a vacuum portion 166 that evacuates the upper chamber 160 and the lower chamber 162 in the closed state, and an atmosphere of the upper chamber 160 and the lower chamber 162. It is provided with an atmosphere opening unit 168 that is open to the public.

As shown in FIG. 7, the upper chamber 160 of the illustrated embodiment includes a circular top plate 170 and a cylindrical side wall 172 hanging from the peripheral edge of the top plate 170. An elevating mechanism 164, which may be composed of an appropriate actuator such as an air cylinder, is mounted on the upper surface of the top plate 170. A pressing roller 174 for pressing the tape 96 of the frame 64'with tape against the back surface 4b of the wafer 4 supported by the wafer table 12 in the accommodation space defined by the lower surface of the top plate 170 and the inner peripheral surface of the side wall 172. A support piece 176 that rotatably supports the pressing roller 174, and a Y-axis feeding means 178 that moves the support piece 176 in the Y-axis direction are arranged.

The Y-axis feeding means 178 has a ball screw 180 connected to the support piece 176 and extending in the Y-axis direction, and a motor 182 for rotating the ball screw 180. Then, the Y-axis feeding means 178 converts the rotational motion of the motor 182 into a linear motion by the ball screw 180 and transmits it to the support piece 176, and moves the support piece 176 along the pair of guide rails 184 extending in the Y-axis direction. Let me.

As shown in FIG. 7, the lower chamber 162 has a cylindrical side wall 186, the upper part of the side wall 186 is open, and the lower part of the side wall 186 is closed. A connection opening 188 is formed in the side wall 186. A vacuum portion 166, which may be composed of an appropriate vacuum pump, is connected to the connection opening 188 via a flow path 190. The flow path 190 is provided with an atmosphere opening portion 168 which may be composed of an appropriate valve capable of opening the flow path 190 to the atmosphere.

The tape crimping means 102 lowers the upper chamber 160 by the elevating mechanism 164 in a state where the tape 96 of the frame with tape 64'is positioned on the back surface 4b of the wafer 4 supported by the wafer table 12, and the side wall of the upper chamber 160. The lower end of the 172 is brought into contact with the upper end of the side wall 186 of the lower chamber 162 to close the upper chamber 160 and the lower chamber 162, and the pressing roller 174 is brought into contact with the taped frame 64'.

Next, the tape crimping means 102 operates the vacuum pump constituting the vacuum portion 166 in a state where the valve constituting the atmosphere opening portion 168 is closed to evacuate the insides of the upper chamber 160 and the lower chamber 162, and then the inside of the upper chamber 160 and the lower chamber 162 is evacuated. And as shown in FIG. 9, the pressing roller 174 is rolled in the Y-axis direction by the Y-axis feeding means 178, so that the tape 96 is crimped to the back surface 4b of the chamber 4 to generate the frame unit U.

When the tape 96 is crimped to the back surface 4b of the wafer 4 by the pressing roller 174, a slight gap is formed between the wafer 4 and the tape 96 at the base of the ring-shaped reinforcing portion 24, but the upper chamber 160 and the lower chamber are formed. Since the wafer 4 and the tape 96 are crimped with the inside of the 162 being evacuated, the pressure in the slight gap between the wafer 4 and the tape 96 is lower than the atmospheric pressure, and after the tape 96 is crimped, the atmosphere opening portion 168 is crimped. When the wafer is released, the tape 96 is pressed against the wafer 4 by the atmospheric pressure. As a result, the gap between the wafer 4 and the tape 96 at the base of the reinforcing portion 24 is eliminated, and the tape 96 is brought into close contact with the back surface 4b of the wafer 4 along the base of the reinforcing portion 24.

As shown in FIGS. 1 and 10, the processing unit 2 further carries out the frame unit U to which the tape 96 of the frame with tape 64'and the back surface 4b of the wafer 4 are crimped by the tape crimping means 102 from the wafer table 12. The reinforcing portion removing means 194 for cutting and removing the ring-shaped reinforcing portion 24 from the wafer 4 of the frame unit carrying-out means 192 and the frame unit U carried out by the frame unit carrying-out means 192, and the ring-shaped reinforcing portion 24 are removed. A ringless unit carrying out means 196 (see FIG. 1) for carrying out the ringless unit from the reinforcing portion removing means 194 and a frame cassette 198 for accommodating the ringless unit carried out by the ringless unit carrying out means 196 are mounted. The frame cassette table 200 (see FIG. 1) is included.

As shown in FIG. 10, the frame unit carrying-out means 192 of the illustrated embodiment has a wafer holding portion 202a for holding the wafer 4 by exposing all or a part of the outer periphery of the wafer 4 and a frame holding portion 202b for holding the frame 64. The frame unit holding unit 202 including the frame unit holding unit 202 and the transporting unit 206 for transporting the frame unit holding unit 202 to the temporary placement table 204 are provided.

The wafer holding portion 202a of the frame unit holding portion 202 includes a circular substrate 208 and a suction piece 210 mounted on the lower surface of the substrate 208. A plurality of suction holes (not shown) are formed on the lower surface of the suction piece 210, and each suction hole is connected to a suction means (not shown). The shape of the suction piece 210 may be, for example, a circular shape smaller than the diameter of the wafer 4. The frame holding portion 202b includes a plurality of protruding pieces 212 (four in the illustrated embodiment) protruding outward in the radial direction at intervals in the circumferential direction from the peripheral edge of the substrate 208 of the wafer holding portion 202a, and the lower surface of the protruding pieces 212. Each suction pad 214 is connected to a suction means (not shown), including a suction pad 214 attached to the.

The transport portion 206 is an X-axis guide member 216 fixed to an appropriate bracket (not shown) and extending in the X-axis direction, and an X-axis movable member supported by the X-axis guide member 216 movably in the X-axis direction. 218, an X-axis feed means (not shown) for moving the X-axis movable member 218 in the X-axis direction, and a Z-axis movable member 220 supported by the X-axis movable member 218 so as to be movable in the Z-axis direction. , A Z-axis feed means (not shown) for moving the Z-axis movable member 220 in the Z-axis direction, a Y-axis movable member 222 supported by the Z-axis movable member 220 so as to be movable in the Y-axis direction, and Y. It includes a Y-axis feed means (not shown) for moving the shaft movable member 222 in the Y-axis direction. The substrate 208 of the wafer holding portion 202a is connected to the tip of the Y-axis movable member 222. Each of the X-axis, Y-axis, and Z-axis feeding means of the transport unit 206 may have a configuration having a ball screw and a motor for rotating the ball screw.

The frame unit carrying-out means 192 is further arranged at a position facing the image pickup unit 224 and sandwiching the wafer 4 with the image pickup unit 224 that images the outer periphery of the wafer 4 of the frame unit U held by the frame unit holding unit 202. It is provided with a lighting unit 400. The imaging unit 224 of the illustrated embodiment is arranged between the wafer table 12 and the temporary placement table 204, and the outer periphery of the wafer 4 of the frame unit U held by the frame unit holding unit 202 is located below the wafer 4. Image from.

The frame unit carrying-out means 192 sucks and holds the wafer 4 from the back surface 4b side (tape 96 side) by the suction piece 210 of the wafer holding portion 202a, and sucks and holds the frame 64 by the suction pad 214 of the frame holding portion 202b. By operating the transport unit 206, the frame unit U held by the frame unit holding unit 202 is carried out from the wafer table 12. When the suction piece 210 of the wafer holding portion 202a sucks and holds the wafer 4, the entire back surface 4b side of the wafer 4 is not covered by the suction piece 210, that is, the suction piece 210 is on the back surface 4b of the wafer 4. There is a portion that is not adsorbed by the wafer, and all or part of the outer periphery of the wafer 4 is exposed.

Further, in the frame unit unloading means 192 of the illustrated embodiment, the transport unit 206 is operated to cover the exposed portion (covered by the suction piece 210) of the outer periphery of the wafer 4 of the frame unit U held by the frame unit holding unit 202. By imaging at least three points in the unbroken portion) with the imaging unit 224, the coordinates of at least three points on the outer periphery of the wafer 4 are measured, and the center coordinates of the wafer 4 are obtained based on the measured coordinates of the three points. In the illustrated embodiment, since all or part of the outer periphery of the wafer 4 sucked and held by the suction piece 210 is exposed, the exposed portion of the outer periphery of the wafer 4 is illuminated by the illumination unit 400 from above the wafer 4. By imaging the exposed portion of the outer periphery of the wafer 4 from below the wafer 4 with the imaging unit 224, the outline of the wafer 4 can be clearly imaged, and the center coordinates of the wafer 4 can be accurately obtained. Then, the frame unit carrying-out means 192 aligns the center of the wafer 4 with the center of the temporary placement table 204, and temporarily places the frame unit U on the temporary placement table 204.

As shown in FIG. 10, the temporary table 204 is arranged at a distance from the wafer table 12 in the X-axis direction. The temporary table 204 of the illustrated embodiment has an annular support portion 226 that supports the outer peripheral surplus region 20 of the wafer 4 of the frame unit U and has a non-contact portion inside the outer peripheral surplus region 20, and an annular support portion 226. It is provided on the outer periphery and includes a frame support portion 228 that supports the frame 64. The frame support portion 228 includes a strong permanent magnet 402 having a stronger magnetic force than the permanent magnet 424 of the first elevating table 420 described later, and a detaching portion 404 that detaches the frame magnetized on the strong permanent magnet 402.

As shown in FIG. 10, the strong permanent magnets 402 are housed in the upper end of the frame body 406 of the frame support portion 228 at intervals in the circumferential direction. Explaining with reference to FIG. 11, the strong permanent magnet 402 of the illustrated embodiment has a columnar main portion 402a in which the frame is magnetized on the upper end surface and an annular flange extending radially outward from the lower end of the main portion 402a. It has a portion 402b. Further, the strong permanent magnet 402 is accommodated in the accommodating hole 406a of the frame body 406 so as to be movable in the vertical direction between the ascending position shown in FIG. 11A and the descending position shown in FIG. 11B. There is. As can be understood by referring to FIG. 11, in the ascending position, the upper surface of the strong permanent magnet 402 and the upper surface of the frame body 406 are flush with each other, and in the descending position, the upper surface of the strong permanent magnet 402 is the frame body. It is located, for example, about 5 mm below the upper surface of the 406. The frame body 406 is made of a non-magnetic material.

As shown in FIG. 11, a partition wall 408 is provided in the vertical intermediate portion of the accommodating hole 406a of the frame body 406, and the partition wall 408 provides an upper accommodating chamber 410 for accommodating the strong permanent magnet 402 and a detaching portion. A storage hole 406a of the frame body 406 is partitioned from the lower storage chamber 412 that houses the 404. A through opening 408a is formed in the central portion of the partition wall 408.

On the upper end side of the upper storage chamber 410, a protruding portion 410a protruding inward in the radial direction is formed. As shown in FIG. 11A, when an upward force is applied to the strong permanent magnet 402 from the detached portion 404, the upper end of the flange portion 402b of the strong permanent magnet 402 is caught on the lower end of the protruding portion 410a. , The strong permanent magnet 402 is positioned in the ascending position. On the other hand, when a downward force is applied to the strong permanent magnet 402 from the detached portion 404, as shown in FIG. 11B, the lower surface of the strong permanent magnet 402 comes into contact with the upper surface of the partition wall 408, and the strong permanent magnet 402. Is positioned in the descending position. Further, in the lower storage chamber 412, an upper opening 412a and a lower opening 412b are formed at intervals in the vertical direction.

Continuing the description with reference to FIG. 11, the detached portion 404 of the illustrated embodiment is fixed to the lower end of the rod 414 and the rod 414 extending downward from the lower end of the strong permanent magnet 402 through the through opening 408a, and the lower side. A piston 416 located in the containment chamber 412, a coil spring 418 located below the piston 416, and a compressed air supply source (not shown) connected to the upper opening 412a of the lower containment chamber 412. Have.

At the detachment portion 404, the supply of compressed air from the compressed air supply source to the lower storage chamber 412 is stopped, and the piston 416 is pushed upward by the coil spring 418 to apply an upward force to the strong permanent magnet 402 to apply an upward force to the frame. The strong permanent magnet 402 is raised with respect to the body 406, and the strong permanent magnet 402 is positioned at an ascending position where the frame 64 mounted on the frame support portion 228 can be magnetized by the strong permanent magnet 402. Further, the detaching portion 404 applies a downward force to the strong permanent magnet 402 by supplying compressed air from the compressed air supply source to the lower accommodating chamber 412 and pushing the piston 416 downward to the frame 406. The strong permanent magnet 402 is lowered, and the strong permanent magnet 402 is positioned at a lowering position where the frame 64 mounted on the frame support portion 228 can be detached from the strong permanent magnet 402. By pushing the piston 416 downward, air is discharged from the lower opening 412b.

As shown in FIG. 10, a plurality of suction holes 229 arranged at intervals in the circumferential direction are formed on the upper surface of the annular support portion 226 of the temporary placement table 204, and each suction hole 229 is a suction means (FIG. 10). Not shown.) Connected to. Further, the annular support portion 226 has an ascending position (position shown in FIG. 10) where the upper surface of the annular support portion 226 and the upper surface of the frame support portion 228 are flush with each other, and the upper surface of the annular support portion 226 is the frame support portion 228. It is configured to be able to move up and down between a lowering position located, for example, about 5 to 10 mm below the upper surface. The lifting means (not shown) for raising and lowering the annular support portion 226 may be an appropriate actuator such as an air cylinder. The radial inner portion of the annular support portion 226 is a circular recess 230 recessed downward. The frame support portion 228 of the temporary placement table 204 is provided with a heater (not shown), and the tape 96 of the frame unit U temporarily placed on the temporary placement table 204 is heated by the heater to soften the tape 96. Therefore, it is preferable that the tape 96 is further brought into close contact with the base of the ring-shaped reinforcing portion 24 by atmospheric pressure.

The processing unit 2 of the illustrated embodiment includes a temporary table transfer unit 232 that conveys the temporary table 204 in the Y-axis direction. The temporary table transport unit 232 includes a Y-axis guide member 234 extending in the Y-axis direction, a Y-axis movable member 236 movably supported by the Y-axis guide member 234 in the Y-axis direction, and a Y-axis movable member 236. A Y-axis feed means 238 for moving in the axial direction is provided. A temporary table 204 is fixed to the upper part of the Y-axis movable member 236. The Y-axis feeding means 238 has a ball screw 240 connected to the Y-axis movable member 236 and extending in the Y-axis direction, and a motor 242 for rotating the ball screw 240. Then, the temporary placement table transport unit 232 converts the rotational motion of the motor 242 into a linear motion by the ball screw 240 and transmits it to the Y-axis movable member 236, and the temporary placement table 204 is moved in the Y-axis direction together with the Y-axis movable member 236. Transport.

As shown in FIG. 1, the reinforcing portion removing means 194 includes a laser processing device 500 for forming a cutting groove by irradiating a laser beam toward the base of a ring-shaped reinforcing portion 24 formed on the outer periphery of the wafer 4, and a cutting groove. The ring-shaped reinforcing portion 24 is provided with a separating portion 248 for separating the reinforcing portion 24. The laser processing apparatus 500 includes a holding means 502 for holding the wafer 4, a laser beam irradiating means 504 for irradiating the boundary portion 22 between the device region 18 of the wafer 4 held by the holding means 502 and the outer peripheral surplus region 20 with a laser beam. A moving means 506 for relatively moving the holding means 502 and the laser beam irradiating means 504 is provided.

As shown in FIG. 1, the holding means 502 of the laser processing apparatus 500 is arranged above the temporary placement table 204 so as to be movable in the X-axis direction and movable in the Z-axis direction. Explaining with reference to FIG. 12, the holding means 502 has an X-axis guide member 258 fixed to an appropriate bracket (not shown) and extending in the X-axis direction, and an X-axis guide member movably movable in the X-axis direction. It includes an X-axis movable member 260 supported by 258 and a Z-axis movable member 262 movably supported by the X-axis movable member 260 in the Z-axis direction. A support shaft 264 extending downward is rotatably supported on the lower surface of the tip of the Z-axis movable member 262, and a first circular lifting table 420 is fixed to the lower end of the support shaft 264.

As shown in FIG. 12B, the first elevating table 420 has a small-diameter wafer holding portion 422 that is smaller than the outer diameter of the wafer 4 and exposes the ring-shaped reinforcing portion 24, and a permanent magnet 424 that magnetizes the frame 64. It has a frame support portion 426 provided with the above, and a space 428 provided between the wafer holding portion 422 and the frame support portion 426 to diffuse the leaked light of the laser beam.

Continuing the description with reference to FIG. 12B, the wafer holding portion 422 is arranged at the center of the lower surface of the first elevating table 420, and the diameter of the wafer holding portion 422 is the device region 18 of the wafer 4 ( It is slightly smaller than the diameter of the circular recess 23). A circular suction chuck 430 formed of a porous material is provided at the lower end of the wafer holding portion 422, and the suction chuck 430 is connected to a suction means (not shown).

The frame support portion 426 is arranged on the outer peripheral portion of the first elevating table 420. At the lower end of the frame support portion 426, a plurality of permanent magnets 424 (four in the illustrated embodiment) are provided at intervals in the circumferential direction. The magnetic force of the permanent magnet 424 is weaker than the magnetic force of the strong permanent magnet 402 of the temporary placement table 204. Further, between the wafer holding portion 422 and the frame support portion 426 on the lower surface of the first elevating table 420, there is an annular recess that is recessed upward, and this recess diffuses the leaked light of the laser beam. Space 428 is configured.

Explaining with reference to FIG. 12A, the moving means 506 of the laser processing apparatus 500 includes an X-axis feeding means (not shown) for moving the X-axis movable member 260 of the holding means 502 in the X-axis direction. , A Z-axis feed means (not shown) that moves the Z-axis movable member 262 of the holding means 502 in the Z-axis direction, and an axis that is attached to the upper surface of the tip of the Z-axis movable member 262 and extends in the Z-axis direction. The motor 266 for rotating the support shaft 264 of the holding means 502 is included. Each of the X-axis and Z-axis feeding means of the moving means 506 may have a structure including a ball screw and a motor for rotating the ball screw. Then, in the moving means 506, when the frame unit U temporarily placed on the temporary placing table 204 is held by the holding means 502 of the laser processing means 500, the holding means 502 is raised and moved in the X-axis direction to the frame. The unit U is positioned above the laser beam irradiating means 504.

As shown in FIG. 10, the laser beam irradiating means 504 of the laser processing apparatus 500 includes a housing 508 arranged adjacent to the temporary table 204 in the X-axis direction. Explaining with reference to FIG. 13, in the housing 508, between the oscillator 510 that oscillates the laser beam LB, the condenser 512 that concentrates the laser beam LB oscillated by the oscillator 510, and the condenser 512 and the oscillator 510. A beam splitter 516 that splits the plasma light P emitted from the region processed by irradiation with the laser beam LB and guides it to the branch path 514, and plasma light detection that is arranged in the branch path 514 and detects the plasma light P. Means 518 and are attached. As shown in FIG. 13, the laser beam irradiating means 504 of the illustrated embodiment reflects the attenuator 520 that adjusts the power of the laser beam LB oscillated by the oscillator 510 and the laser beam LB whose power is adjusted by the attenuator 520 and transmitted through the beam splitter 516. Includes a mirror 522 that leads to the condenser 512. In FIG. 13, for convenience, the condenser 512 is shown in the form of a condenser lens.

The oscillator 510 and the attenuator 520 are electrically connected to a control means 524 composed of a computer, and the operation is controlled by the control means 524. As shown in FIG. 13, the control means 524 is electrically connected to the power setting means 526 for selecting the type of material and setting the power of the laser beam LB. The power setting means 526 is provided, for example, on an operation panel (not shown) for operating the processing device 2, and the operator selects the type of material through the power setting means 526 provided on the operation panel. Then, the power of the laser beam LB can be set.

For example, when the operator selects silicon as the material type through the power setting means 526, 1.0 W is set by the power setting means 526 as the power at which appropriate laser processing is performed on the silicon, and aluminum is selected. If so, the power is set to 2.0W, and if copper is selected, the power is set to 2.5W. The combination of the type of material and the power of the laser beam LB is arbitrarily determined and is not limited to the above-mentioned combination.

Then, the control means 524 controls the attenuator 520 to adjust the power of the laser beam LB so as to be the power set by the power setting means 526. As described above, the power setting means 526 may set the power according to the material selected by the operator, but the operator can set an arbitrary power together with the material through the power setting means 526. It may be.

The beam splitter 516 transmits light having a wavelength (for example, 355 nm) of the laser beam LB oscillated by the oscillator 510, and reflects light having a wavelength other than the wavelength of the laser beam LB (for example, plasma light P) to the branch path 514. It may consist of a guiding dichroic mirror.

The plasma light detecting means 518 includes a diffraction grating 528 that disperses the plasma light P guided to the branch path 514 by the beam splitter 516 in a different direction for each wavelength, and a plasma light that is dispersed in a different direction for each wavelength by the diffraction grating 528. It includes an image sensor 530 that receives P.

The image sensor 530 has a plurality of light receiving elements arranged in a straight line. Each light receiving element receives plasma light P dispersed in different directions for each wavelength, and the wavelength of the plasma light P to be received differs depending on the position of the light receiving element. The image sensor 530 is electrically connected to the control means 524, and outputs a signal indicating the light intensity of the plasma light P received by each light receiving element to the control means 524. The plasma light detecting means 518 does not necessarily have to be configured to detect the plasma light P guided to the branch path 514 by the beam splitter 516. That is, the plasma light detection means 518 may not be arranged in the branch path 514. For example, the plasma light detecting means 518 may be arranged at a position where the plasma light P emitted from the region processed by the irradiation of the laser beam LB can be directly detected. In this case, the beam splitter 516 may be omitted from the laser beam irradiating means 504.

When a signal is output from the image sensor 530 of the plasma light detection means 518 to the control means 524, the control means 524 is laser-processed by irradiation with a laser beam LB based on the plasma light P detected by the image sensor 530. Identify the material of the area. For example, as shown in FIGS. 14 (a) and 14 (b), when the signal S1 having a high light intensity of the component having a wavelength of 251 nm among the detected plasma light P is output, laser processing is performed. The material of the region is silicon, aluminum when the signal S2 having a high light intensity of the component having a wavelength of 395 nm is output, and copper when the signal S3 having a high light intensity of the component having a wavelength of 515 nm is output. If present, the control means 524 identifies the material. A table showing the relationship between the wavelength of the plasma light P and the material of the region subjected to the laser processing is stored in advance in the control means 524.

Then, when the type of the material specified based on the plasma light P detected by the plasma light detecting means 518 and the type of the material selected by the power setting means 526 are different, the control means 524 causes an error transmitting means 532 (FIG. FIG. 13) is activated to generate an error. The error transmitting means 532 is electrically connected to the control means 524, and may be, for example, a monitor that displays an error message, a speaker that emits a warning sound related to an error, or a warning lamp that lights up or blinks in the case of an error.

Alternatively, instead of issuing an error, when the type of the material specified based on the plasma light P detected by the plasma light detecting means 518 and the type of the material selected by the power setting means 526 are different, the control means. The 524 may control the attenuator 520 to adjust the power of the laser beam LB to an appropriate value according to the material (for example, the value shown in the table of FIG. 14B).

Explaining with reference to FIG. 10, the laser processing apparatus 500 has a suction nozzle 534 for sucking debris generated when the wafer 4 is irradiated with the laser beam LB, and a suction means connected to the suction nozzle 534 (not shown). .) And including. As shown in FIG. 10, the concentrator 512 extends upward from the upper surface of the housing 508 toward the suction nozzle 534, whereby debris generated during irradiation with the laser beam LB is collected by the concentrator 512. It is suppressed from falling to. Further, the suction nozzle 534 extends upward from the upper surface of the housing 508 toward the condenser 512.

Then, in the laser processing apparatus 500, the frame 64 of the frame unit U in which the tape 96 is heated by the heater of the frame holding portion 228 of the temporary placement table 204 and the tape 96 is in close contact with the base of the ring-shaped reinforcing portion 24 is first placed. The Z-axis movable member 262 and the X-axis movable member 260 are moved after being held by the permanent magnet 424 of the frame support portion 426 of the elevating table 420 and the wafer 4 being attracted and held by the suction chuck 430 of the weight holding portion 422. The frame unit U held by the first elevating table 420 is raised and moved in the X-axis direction to be positioned above the laser beam irradiating means 504.

When the frame unit U is held by the first elevating table 420 of the holding means 502, the strong permanent magnet 402 of the frame holding portion 228 of the temporary placement table 204 is positioned in the descending position to be strongly permanent from the frame 64. The first elevating table 420 in which the magnets 402 are separated and the frame 64 mounted on the temporary placement table 204 is in contact with the frame 64 rather than the magnetic force acting from the strong permanent magnet 402 of the temporary placement table 204. Make sure that the magnetic force acting from the permanent magnet 424 is stronger.

Further, as shown in FIGS. 13 and 15, the laser processing apparatus 500 is formed on the outer periphery of the wafer 4 while rotating the frame unit U held by the first elevating table 420 by the motor 266 of the moving means 506. A laser beam LB is irradiated toward the base of the ring-shaped reinforcing portion 24, and a ring-shaped cutting groove 256 is formed along the base of the reinforcing portion 24 by ablation processing. Further, the laser processing apparatus 500 sucks the debris generated by the ablation processing by the suction nozzle 534.

Then, in the control means 524, when the plasma light P is no longer detected by the plasma light detection means 518 (when the signal is no longer output from the image sensor 530), the cutting groove 256 is formed in the wafer 4 (the wafer 4 is formed). It is determined that the laser beam is completely cut off), and the irradiation of the laser beam LB is stopped. Therefore, even though the wafer 4 has already been cut, it is possible to prevent the laser beam LB from being irradiated.

Further, the moving means 506 of the laser processing apparatus 500 moves the frame unit U having the cutting groove 256 formed at the base of the reinforcing portion 24 in the X-axis direction and the Z-axis direction and moves them to the temporary placement table 204. Debris adheres to the outer periphery of the wafer 4 due to the irradiation of the laser beam LB, and when the frame unit U is handed over from the first elevating table 420 to the temporary placement table 204, only the strong permanent magnet 402 is allowed to act. It is preferable to stop the suction of the annular support portion 226 of the temporary placement table 204. This prevents debris from adhering to the suction hole 229 of the annular support portion 226. Further, from the viewpoint of preventing debris from adhering to the suction hole 229, it is desirable to position the annular support portion 226 in the descending position.

As shown in FIG. 1, the separation unit 248 is arranged at a distance from the holding means 502 in the Y-axis direction in the movable range of the temporary placement table 204 in the Y-axis direction. Explaining with reference to FIGS. 16 and 18, the separation unit 248 and the ultraviolet irradiation unit 270 (see FIG. 16) that irradiates the tape 96 corresponding to the cutting groove 256 with ultraviolet rays to reduce the adhesive force of the tape 96. A second elevating table 272 (see FIG. 16) that exposes the ring-shaped reinforcing portion 24 to the outer periphery to suck and hold the inside of the wafer 4 and supports the frame 64, and the outer periphery of the ring-shaped reinforcing portion 24. It includes a separator 274 (see FIG. 16) that acts to separate the ring-shaped reinforcing portion 24, and a disposal unit 276 (see FIG. 18) from which the separated ring-shaped reinforcing portion 24 is discarded.

As shown in FIG. 16, the separation portion 248 of the illustrated embodiment has a Z-axis guide member 278 fixed to an appropriate bracket (not shown) and extending in the Z-axis direction, and a Z-axis movable in the Z-axis direction. A Z-axis movable member 280 supported by the guide member 278 and a Z-axis feeding means (not shown) for moving the Z-axis movable member 280 in the Z-axis direction are included. The Z-axis feed means may have a configuration including a ball screw connected to the Z-axis movable member 280 and extending in the Z-axis direction, and a motor for rotating the ball screw.

A support piece 282 is supported on the lower surface of the tip of the Z-axis movable member 280, and a support shaft 286 is rotatably supported, and the second elevating table 272 is connected to the support shaft 286. .. A motor 284 that rotates the second elevating table 272 together with the support shaft 286 is attached to the upper surface of the tip of the Z-axis movable member 280. The support piece 282 of the illustrated embodiment is provided with a pair of the ultraviolet irradiation units 270 at intervals in the Y-axis direction.

The second elevating table 272 is circular, and the diameter of the second elevating table 272 is slightly smaller than the diameter of the device region 18 (circular recess 23) of the wafer 4. A plurality of suction holes (not shown) are formed on the lower surface of the second elevating table 272, and each suction hole is connected to the suction means.

Further, the separator 274 is attached to the support piece 282. The separator 274 includes a pair of movable pieces 288 that are movably arranged in the longitudinal direction of the support piece 282 at intervals on the lower surface of the support piece 282, and a pair of feeding means 290 that move the pair of movable pieces 288. include. Each of the pair of feeding means 290 may be composed of an appropriate actuator such as an air cylinder or an electric cylinder.

The separator 274 includes a pair of sandwiching rollers 292a and 292b supported by 288 on each movable piece at intervals in the vertical direction, and a Z-axis feeding means 294 for moving the upper sandwiching roller 292a in the Z-axis direction. .. The Z-axis feed means 294 may be composed of an appropriate actuator such as an air cylinder or an electric cylinder. The sandwiching rollers 292a and 292b are rotatably supported by a movable piece 288 about an axis extending in the X-axis direction. A pressing roller 298 is mounted on the upper sandwiching roller 292a via a support shaft 296.

Explaining with reference to FIG. 18, the disposal unit 276 includes a belt conveyor 300 that conveys the separated ring-shaped reinforcing portion 24 and a dust box 302 that houses the ring-shaped reinforcing portion 24 conveyed by the belt conveyor 300. And include. The belt conveyor 300 has appropriate actuators (shown) at a collection position extending substantially horizontally (position shown by a solid line in FIG. 18) and a standby position extending substantially vertically (position shown by a two-dot chain line in FIG. 18). Not positioned by). In FIG. 18, a door 304 to which a handle 304a is attached is provided on the side surface of the dust box 302 on the front side in the X-axis direction. Inside the dust box 302, a crusher (not shown) for crushing the collected ring-shaped reinforcing portion 24 is attached. In the dust box 302, by grasping the handle 304a and opening the door 304, the crushed debris of the ring-shaped reinforcing portion 24 housed in the dust box 302 can be taken out.

When the temporary placement table 204 in which the frame unit U having the cutting groove 256 formed at the base of the reinforcing portion 24 is temporarily placed is positioned below the separation portion 248 by the temporary placement table transport portion 232, the separation portion 248 is shown in FIG. As shown in 17, the back surface 4b side of the wafer 4 of the frame unit U is sucked and held by the second elevating table 272, and the frame 64 is sandwiched by the sandwiching rollers 292a and 292b of the separator 274, and then a pair of ultraviolet irradiation units. The adhesive force of the tape 96 attached to the ring-shaped reinforcing portion 24 is reduced by irradiating ultraviolet rays from the 270, and the ring-shaped reinforcing portion 24 is pressed downward by the pressing roller 298 against the separator 274. The ring-shaped reinforcing portion 24 is separated from the frame unit U by rotating the frame unit U together with the support shaft 286 and the second elevating table 272 by the motor 284. The separated reinforcing portion 24 is conveyed to the dust box 302 by the belt conveyor 300 and collected. When separating the reinforcing portion 24, the separator 274 may be rotated with respect to the frame unit U.

As shown in FIG. 1, the ringless unit carrying-out means 196 is arranged adjacent to the reinforcing portion removing means 194. Explaining with reference to FIGS. 19 and 20, the ringless unit unloading means 196 of the illustrated embodiment faces the ringless unit supported by the second elevating table 272 and holds the frame 64. A reversing mechanism 308 (see FIG. 19) that moves toward the frame cassette table 200 and inverts the frame holding portion 306, and a ringless unit that is inverted by the inversion mechanism 308 and the surface 4a of the wafer 4 faces upward. A push-in portion in which the ringless unit support portion 310 (see FIG. 20) to be supported and the ringless unit supported by the ringless unit support portion 310 are inserted into and accommodated in the frame cassette 198 placed on the frame cassette table 200. It is provided with 312 (see FIG. 20).

As shown in FIG. 19, the reversing mechanism 308 includes a Y-axis guide member 314 extending in the Y-axis direction, a Y-axis movable member 316 movably supported by the Y-axis guide member 314 in the Y-axis direction, and a Y-axis movable member. A Y-axis feed means (not shown) that moves the 316 in the Y-axis direction, an arm 318 that is movably movable in the Z-axis direction and supported by the Y-axis movable member 316, and the arm 318 are moved in the Z-axis direction. Includes Z-axis feed means (not shown). Each of the Y-axis and Z-axis feeding means of the reversing mechanism 308 may have a configuration including a ball screw and a motor for rotating the ball screw.

The frame holding portion 306 is supported upside down on the arm 318, and a motor 320 for turning the frame holding portion 306 upside down is attached to the arm 318. The frame holding portion 306 of the illustrated embodiment includes a substrate 324 rotatably supported by an arm 318 via a pair of rotating shafts 322, and a plurality of suction pads 326 attached to one side of the substrate 324, respectively. The suction pad 326 is connected to a suction means (not shown). Further, one of the rotating shafts 322 is connected to the motor 320.

The reversing mechanism 308 sucks and holds the lower surface of the frame 64 of the ringless unit U'supported by the second elevating table 272 with the suction pad 326 with the suction pad 326 facing up, and the second elevating table. Receive the ringless unit U'from 272. Further, the reversing mechanism 308 does not have a ring held by the frame holding portion 306 by reversing the frame holding portion 306 by the motor 320 to turn the surface 4a of the wafer 4 upward and then moving the Y-axis movable member 316. Move unit U'toward the frame cassette table 200.

As shown in FIG. 20, the ringless unit support portion 310 of the illustrated embodiment is paired with a pair of support plates 328 that are movably supported in the X-axis direction via an appropriate bracket (not shown). Includes spacing adjusting means (not shown) for adjusting the spacing of the support plates 328 in the X-axis direction. The interval adjusting means may be composed of an appropriate actuator such as an air cylinder or an electric cylinder.

A heater (not shown) is mounted on a pair of support plates 328 that support the ringless unit U'. In a state where the distance between the pair of support plates 328 is narrowed, the pair of support plates 328 is formed by heating the tape 96 of the ringless unit U'with a heater to remove the reinforcing portion 24. It is designed to smooth out sagging and wrinkles.

Continuing the description with reference to FIG. 20, the push-in portion 312 of the illustrated embodiment is supported by a Y-axis guide member 330 extending in the Y-axis direction and a Y-axis guide member 330 movably supported in the Y-axis direction. It includes a shaft movable member 332 and a Y-axis feed means (not shown) for moving the Y-axis movable member 332 in the Y-axis direction. The Y-axis movable member 332 has a base portion 334 supported by the Y-axis guide member 330, a support column 336 extending upward from the upper surface of the base portion 334, and a pressing piece 338 attached to the upper end of the support column 336. The Y-axis feed means of the pushing portion 312 may have a configuration including a ball screw connected to the Y-axis movable member 332 and extending in the Y-axis direction, and a motor for rotating the ball screw.

As shown in FIG. 21, the ringless unit support portion 310 increases the distance between the pair of support plates 328 by the spacing adjusting means before receiving the ringless unit U', and then holds the ringless unit U held by the suction pad 326. 'Receive. Then, when the ringless unit support portion 310 receives the ringless unit U', the push-in portion 312 moves the Y-axis movable member 332 in the Y-axis direction by the Y-axis feed means to the ringless unit support portion 310. The supported ringless unit U'is inserted into and accommodated in the frame cassette 198 placed on the frame cassette table 200 by the pressing piece 338.

In the frame cassette 198 shown in FIGS. 1 and 21, a plurality of ringless units U'are housed at intervals in the vertical direction with the surface 4a of the wafer 4 facing upward. As shown in FIGS. 20 and 21, the frame cassette table 200 includes a mounting portion 340 on which the frame cassette 198 is mounted, and an elevating portion 342 that raises and lowers the mounting portion 340 to position it at an arbitrary height. The elevating portion 342 may have a configuration including a ball screw connected to the mounting portion 340 and extending in the Z-axis direction, and a motor for rotating the ball screw.

Next, using the processing unit 2 as described above, the dicing tape 96 is attached to the back surface 4b of the wafer 4 in which the ring-shaped reinforcing portion 24 is formed convexly on the back surface 4b corresponding to the outer peripheral surplus region 20. A processing method of cutting the ring-shaped reinforcing portion 24 and removing the ring-shaped reinforcing portion 24 from the wafer 4 will be described.

In the illustrated embodiment, first, as shown in FIGS. 1 and 3, a wafer cassette mounting step of mounting a wafer cassette 6 containing a plurality of wafers 4 on a wafer cassette table 8 is performed. A plurality of wafers 4 are housed in the cassette 6 with the surface 4a facing upward at intervals in the vertical direction.

Further, as shown in FIGS. 1 and 5, a frame accommodating step of accommodating a plurality of ring-shaped frames 64 having an opening 64a for accommodating the wafer 4 in the frame accommodating means 66 is carried out. The frame accommodating step may be carried out before the wafer cassette mounting step, or may be carried out after the wafer cassette mounting step.

In the frame accommodating step, after lowering the elevating plate 74 of the frame accommodating means 66 to an arbitrary position, the handle 76a is grasped to open the door 76, and a plurality of frames 64 are laminated and accommodated on the upper surface of the elevating plate 74. .. Further, the height of the elevating plate 74 is appropriately adjusted, and the uppermost frame 64 is positioned at a position where it can be carried out by the frame carrying out means 68.

After carrying out the wafer cassette mounting step and the frame accommodating step, the wafer carrying-out step of carrying out the wafer 4 from the wafer cassette 6 placed on the wafer cassette table 8 is carried out.

Explaining with reference to FIG. 3, in the wafer unloading process, first, the Y-axis feeding means 34 of the wafer unloading means 10 is operated, and the Y-axis movable member 32 is positioned in the vicinity of the wafer cassette table 8. Next, the transfer arm 42 is driven to position the hand 44 with the air ejection port 46 facing upward on the back surface 4b side (lower side) of the wafer 4 in the wafer cassette 6. When the hand 44 is positioned on the back surface 4b side of the wafer 4, a gap is provided between the back surface 4b of the wafer 4 and the hand 44, and each guide pin 48 is positioned radially outward.

Next, compressed air is ejected from the air ejection port 46 of the hand 44 to generate a negative pressure on one side of the hand 44 by the Bernoulli effect, and the wafer 4 is suction-supported from the back surface 4b side by the hand 44 in a non-contact manner. Next, each guide pin 48 is moved inward in the radial direction, and the horizontal movement of the wafer 4 suction-supported by the hand 44 is restricted by each guide pin 48. Then, the Y-axis movable member 32 and the transfer arm 42 of the wafer carrying-out means 10 are moved, and the wafer 4 sucked and supported by the hand 44 is carried out from the wafer cassette 6.

After carrying out the wafer carry-out step, it is preferable to carry out a notch detection step for detecting the position of the notch 26 of the wafer 4. In the notch detection step, as shown in FIG. 4, the outer periphery of the wafer 4 sucked and supported by the hand 44 is positioned between the light emitting element 52 and the light receiving element 54 of the notch detecting means 50. Next, the position of the notch 26 of the wafer 4 is detected by rotating the wafer 4 with the drive source via the guide pin 48. This makes it possible to adjust the orientation of the wafer 4 to any orientation.

After carrying out the notch detection step, the wafer support step of supporting the surface 4a side of the wafer 4 carried out by the wafer carrying-out means 10 with the wafer table 12 is carried out.

Explaining with reference to FIG. 3, in the wafer support step, first, the hand 44 of the wafer carrying-out means 10 is turned upside down and the surface 4a of the wafer 4 is turned downward. Next, the Y-axis movable member 32 and the transfer arm 42 of the wafer carrying-out means 10 are moved, and the outer peripheral excess region 20 of the surface 4a of the wafer 4 suction-supported by the hand 44 is brought into contact with the annular support portion 56 of the wafer table 12. At this time, since the device region 18 on the surface 4a of the wafer 4 is located in the recess 62 of the wafer table 12, the device 14 and the wafer table 12 do not come into contact with each other, and damage to the device 14 is prevented.

Next, the suction means of the wafer table 12 is operated to generate a suction force in each suction hole 60 to suck and hold the outer peripheral excess region 20 of the surface 4a of the wafer 4. Next, the suction support of the wafer 4 by the hand 44 is released, and the hand 44 is separated from the wafer table 12. In this way, the wafer 4 is delivered from the wafer carrying-out means 10 to the wafer table 12. Since the wafer 4 delivered to the wafer table 12 is suction-held by each suction hole 60, the position of the wafer 4 does not shift.

Further, after the wafer cassette mounting step and the frame accommodating step are carried out, a frame carrying-out step of carrying out the frame 64 from the frame accommodating means 66 is carried out in parallel with the wafer carrying-out step and the wafer supporting step.

Explaining with reference to FIG. 5, in the frame unloading process, first, the X-axis movable member 84 and the Z-axis movable member 86 of the frame unloading means 68 are moved, and the uppermost frame 64 housed in the frame accommodating means 66. The suction pad 92 of the holding portion 88 is brought into contact with the upper surface of the holding portion 88. Next, the suction means of the frame carrying-out means 68 is operated to generate a suction force in the suction pad 92, so that the uppermost frame 64 is sucked and held by the suction pad 92. Then, the X-axis movable member 84 and the Z-axis movable member 86 of the frame carrying-out means 68 are moved, and the uppermost frame 64 sucked and held by the suction pad 92 of the holding portion 88 is carried out from the frame accommodating means 66.

After carrying out the frame carrying-out step, a frame supporting step of supporting the frame 64 carried out by the frame carrying-out means 68 with the frame table 70 is carried out.

Continuing the description with reference to FIG. 5, in the frame support step, first, the X-axis movable member 84 and the Z-axis movable member 86 of the frame carrying-out means 68 are moved, and the frame 64 sucked and held by the suction pad 92 is used as a frame table. It is brought into contact with the upper surface of 70. At this time, the frame table 70 is positioned at the descending position (the position shown by the solid line in FIG. 5). Next, the suction force of the suction pad 92 of the frame carrying-out means 68 is released, and the frame 64 is placed on the frame table 70. Then, the X-axis movable member 84 and the Z-axis movable member 86 of the frame carrying-out means 68 are moved, and the holding portion 88 is separated from above the frame table 70.

After carrying out the frame support step, the tape sticking step of sticking the tape 96 to the frame 64 is carried out.

Explaining with reference to FIG. 6, in the tape attaching step, first, the frame table 70 is moved from the lowered position (the position shown in FIG. 6A) to the ascending position where the tape 96 can be attached to the frame 64 (FIG. 6). Before moving to the position shown in (b), the tape 96 is pulled out from the roll tape 96R and the tape 96 from which the release paper 116 is peeled off is positioned above the frame table 70. The adhesive surface of the tape 96 located above the frame table 70 faces downward.

Next, the frame table 70 is raised to such an extent that the tape 96 can be pressed against the frame 64 from above by the pressing roller 132 of the crimping portion 110 of the tape attaching means 98. Then, the pressing roller 132 is rolled in the Y-axis direction while pressing the adhesive surface of the tape 96 against the frame 64 with the pressing roller 132. As a result, the tape 96 drawn from the roll tape 96R by the tape pulling out portion 108 can be crimped to the frame 64.

Next, the cutter 144 and the pressing roller 146 of the cutting portion 112 of the tape attaching means 98 are lowered, the cutter 144 is pressed against the tape 96 on the frame 64, and the frame 64 is pressed from above the tape 96 by the pressing roller 146. Next, the arm piece 140 is rotated by the motor 138, and the cutter 144 and the pressing roller 146 are moved along the frame 64 in a circular motion. As a result, the tape 96 protruding from the outer periphery of the frame 64 can be cut along the frame 64. Further, since the frame 64 is pressed from above the tape 96 by the pressing roller 146, the misalignment of the frame 64 and the tape 96 is prevented when the tape 96 is cut. The used tape 96 having the circular opening 120 formed thereof is wound by the tape winding portion 106.

After performing the tape attaching step, the frame 64 to which the tape 96 is attached is conveyed to the wafer table 12, and the opening 64a of the frame 64 is positioned on the back surface 4b of the wafer 4 supported by the wafer table 12 and attached with tape. A frame transfer step with tape is carried out in which the frame 64'is placed on the wafer table 12.

In the frame transfer step with tape, first, the frame table 70 is moved from the ascending position to the descending position. Next, the Y-axis movable member 150 and the Z-axis movable member 152 of the frame transporting means 100 with tape (see FIG. 5) are moved and supported by the frame table 70 with the adhesive surface of the tape 96 facing downward. Each suction pad 158 of the holding portion 154 of the frame transporting means 100 with tape is brought into contact with the upper surface of the frame 64'with tape (see FIG. 7).

Next, the suction means of the frame transporting means 100 with tape is operated to generate a suction force on the suction pad 158, so that the upper surface of the frame 64'with tape is sucked and held by the suction pad 158. Next, the Y-axis movable member 150 and the Z-axis movable member 152 of the frame transporting means 100 with tape are moved, and the frame with tape 64'suctioned and held by the suction pad 158 is carried out from the frame table 70.

Next, the frame with tape 64'suctioned and held by the suction pad 158 of the frame conveying means 100 with tape is conveyed to the wafer table 12, and as shown in FIG. 7, the frame 64 is attached to the back surface 4b of the wafer 4 supported by the wafer table 12. The opening portion 64a of the above is positioned so that the frame with tape 64'is brought into contact with the frame support portion 58 of the wafer table 12. At this time, the adhesive surface of the tape 96 of the frame with tape 64'is facing downward, and the back surface 4b of the wafer 4 is facing upward and facing the adhesive surface of the tape 96.

Next, the suction force of the suction pad 158 of the frame transport means 100 with tape is released, and the frame 64'with tape is placed on the frame support portion 58 of the wafer table 12. Then, the Y-axis movable member 150 and the Z-axis movable member 152 of the frame transport means 100 with tape are moved, and the holding portion 154 is separated from above the wafer table 12.

After carrying out the frame transfer step with tape, the tape crimping step of crimping the tape 96 of the frame with tape 64'to the back surface 4b of the wafer 4 is carried out.

Explaining with reference to FIGS. 7 to 9, in the tape crimping step, first, the upper chamber 160 is lowered by the elevating mechanism 164 of the tape crimping means 102, and the lower end of the side wall 172 of the upper chamber 160 is the side wall 186 of the lower chamber 162. Contact the top of the chamber. As a result, the upper chamber 160 and the lower chamber 162 are closed, and the pressing roller 174 is brought into contact with the taped frame 64'. Then, as shown in FIG. 8, the upper end of the ring-shaped reinforcing portion 24 of the wafer 4 is attached to the adhesive surface of the tape 96 of the frame with tape 64'.

Next, the vacuum portion 166 is operated with the atmosphere opening portion 168 of the tape crimping means 102 closed to evacuate the insides of the upper chamber 160 and the lower chamber 162. Next, as shown in FIGS. 8 and 9, the tape 96 is crimped to the back surface 4b of the wafer 4 by rolling the pressing roller 174 of the tape crimping means 102 in the Y-axis direction. As a result, the frame unit U in which the back surface 4b of the wafer 4 and the tape 96 are crimped can be generated. Next, the atmospheric opening portion 168 is opened, and the tape 96 is brought into close contact with the back surface 4b of the wafer 4 along the base of the ring-shaped reinforcing portion 24 by atmospheric pressure. Then, the upper chamber 160 is raised by the elevating mechanism 164. By making the inside of the upper chamber 160 and the lower chamber 162 vacuum, the suction force of the wafer 4 by the wafer table 12 is lost, but when the upper chamber 160 and the lower chamber 162 are closed, the wafer is closed. Since the upper end of the ring-shaped reinforcing portion 24 of 4 is attached to the adhesive surface of the tape 96 of the frame with tape 64', the position of the wafer 4 does not shift in the tape crimping step.

After carrying out the tape crimping step, the frame unit carrying-out step of carrying out the frame unit U to which the tape 96 of the frame with tape 64'and the back surface 4b of the wafer 4 are crimped is carried out from the wafer table 12 is carried out.

Explaining with reference to FIG. 5, in the frame unit unloading process, first, the transport unit 206 of the frame unit unloading means 192 is operated, and the lower surface of the suction piece 210 of the wafer holding portion 202a of the frame unit holding portion 202 is formed by the wafer 4. The tape 96 on the back surface 4b side is brought into contact with the tape 96, and the suction pad 214 of the frame holding portion 202b is brought into contact with the frame 64.

Next, a suction force is generated in the suction piece 210 of the wafer holding portion 202a and the suction pad 214 of the frame holding portion 202b, and the suction piece 210 of the wafer holding portion 202a is exposed in a state where all or a part of the outer periphery of the wafer 4 is exposed. The wafer 4 is sucked and held from the back surface 4b side (tape 96 side), and the frame 64 is sucked and held by the suction pad 214 of the frame holding portion 202b. Next, the suction holding of the wafer 4 by the wafer table 12 is released. Then, the transport unit 206 is operated, and the frame unit U held by the frame unit holding unit 202 is carried out from the wafer table 12.

After carrying out the frame unit carry-out step, the center of the wafer 4 is aligned with the center of the temporary placement table 204, and the temporary placement step of temporarily placing the frame unit U on the temporary placement table 204 is carried out.

To explain with reference to FIG. 10, in the temporary placement step, first, the frame unit U held by the frame unit holding unit 202 is positioned above the image pickup unit 224. Next, the transport unit 206 of the frame unit unloading means 192 is operated, and at least three exposed portions on the outer periphery of the wafer 4 of the frame unit U held by the frame unit holding unit 202 are imaged by the image pickup unit 224. When the wafer 4 is imaged from below by the image pickup unit 224, the wafer 4 is illuminated by the illumination unit 400 from above the wafer 4. As a result, the coordinates of at least three points on the outer circumference of the wafer 4 are measured. Next, the center coordinates of the wafer 4 are obtained based on the measured coordinates of the three points. Since the wafer 4 sucked and held by the suction piece 210 of the wafer holding portion 202a is exposed in whole or in part, the illumination unit 400 illuminates the exposed portion of the outer periphery of the wafer 4 from above and the image pickup unit. By imaging the exposed portion of the outer periphery of the wafer 4 from below with the 224, the outline of the wafer 4 can be clearly imaged, and the center coordinates of the wafer 4 can be accurately obtained.

Next, the transport portion 206 is operated, the center of the wafer 4 is positioned at the center of the annular support portion 226 of the temporary placement table 204, and the outer peripheral excess region of the surface 4a of the wafer 4 is placed on the upper surface of the annular support portion 226 of the temporary placement table 204. 20 is brought into contact with the frame 64, and the lower surface of the frame 64 is brought into contact with the upper surface of the frame support portion 228 of the temporary placement table 204, and the frame 64 is held by the magnetic force of the strong permanent magnet 402. At this time, each of the strong permanent magnet 402 and the annular support portion 226 is positioned in the ascending position. Next, by operating the suction means of the temporary placement table 204 and generating suction force in each suction hole 229, the outer peripheral excess region 20 of the surface 4a of the wafer 4 is suction-held. Further, at this time, the surface 4a of the wafer 4 faces downward, but since the device area 18 is located in the recess 230 of the temporary placement table 204, the device 14 and the temporary placement table 204 do not come into contact with each other. Damage to the device 14 is prevented.

Next, the suction holding of the wafer 4 by the wafer holding portion 202a is released, the suction holding of the frame 64 by the frame holding portion 202b is released, and the frame unit U is delivered from the frame unit carrying-out means 192 to the temporary placement table 204. Next, the heater of the frame support portion 228 is operated, and the tape 96 of the frame unit U temporarily placed on the temporary placement table 204 is heated by the heater. As a result, the tape 96 is softened and the tape 96 is brought into close contact with the base of the ring-shaped reinforcing portion 24 of the wafer 4.

After carrying out the temporary placement step, a reinforcing portion removing step of cutting and removing the ring-shaped reinforcing portion 24 from the wafer 4 of the frame unit U carried out by the frame unit carrying-out means 192 is carried out.

Explaining with reference to FIGS. 1, 10 and 12, in the reinforcing portion removing step, first, the X-axis movable member 260 and the Z-axis movable member 262 of the holding means 502 of the laser processing apparatus 500 are moved to temporarily place the table. The lower surface of the permanent magnet 424 of the first elevating table 420 is brought into contact with the upper surface of the frame 64 of the frame unit U temporarily placed on the 204, the frame 64 is held by the magnetic force of the permanent magnet 424, and the lower surface of the suction chuck 430 is held. Is in contact with the back surface 4b side (tape 96 side) of the wafer 4, and the wafer 4 is held by the suction force of the suction chuck 430.

Next, the strong permanent magnet 402 of the temporary placement table 204 is positioned in the descending position, the attractive force of the annular support portion 226 is released, and then the first elevating table 420 that attracts and holds the frame unit U is raised. As described above, the magnetic force of the permanent magnet 424 of the first elevating table 420 is weaker than the magnetic force of the strong permanent magnet 402 of the temporary placement table 204, and when the strong permanent magnet 402 is positioned in the descending position, the strong permanent magnet from the frame 64 Since the 402 is separated, the magnetic force of the strong permanent magnet 402 acting on the frame 64 is weakened, and the frame unit U can be easily separated from the temporary placement table 204.

Next, the X-axis movable member 260 and the Z-axis movable member 262 of the holding means 502 are operated, and as shown in FIGS. 13 and 15, the frame unit U held by the first elevating table 420 is placed above the laser beam irradiating means 504. Position it. Next, the condensing point of the laser beam LB is positioned at the base of the ring-shaped reinforcing portion 24 of the wafer 4 of the frame unit U.

Next, while rotating the first elevating table 420 and the frame unit U by the motor 266 of the moving means 506, the laser beam LB set to an appropriate power by the power setting means 526 is applied to the base of the ring-shaped reinforcing portion 24 of the wafer 4. Irradiate to. As a result, the base of the ring-shaped reinforcing portion 24 of the wafer 4 can be ablated to form a ring-shaped cutting groove 256. Since the leaked light of the laser beam LB transmitted through the wafer 4 and the tape 96 is diffused in the space 428 between the wafer holding portion 422 and the frame support portion 426, the leakage light causes an adverse effect on the device 14 of the wafer 4. It will be reduced. Further, when irradiating the wafer 4 with the laser beam LB, the suction means of the laser beam irradiating means 504 is operated to generate a suction force in the suction nozzle 534, and the debris generated by the ablation process is sucked by the suction nozzle 534. Then, the control means 524 determines that the cutting groove 256 is formed in the wafer 4 when the plasma light P is no longer detected by the plasma light detection means 518, and stops the irradiation of the laser beam LB. Therefore, even though the wafer 4 has already been cut, it is possible to prevent the laser beam LB from being irradiated.

When irradiating the wafer 4 with the laser beam LB, the following processing conditions can be set, for example.
Wavelength of laser beam: 355 nm
Laser beam power: 1-2.5W
Repeat frequency of laser beam: 100kHz
Motor rotation speed: 60 rpm

When the wafer 4 is irradiated with the laser beam LB, the type of material specified by the control means 524 based on the plasma light P detected by the plasma light detection means 518 and the type of material selected by the power setting means 526 are If they are different, an error is transmitted from the error transmitting means 532. Thereby, the operator can correct the power of the laser beam LB to an appropriate value according to the material of the region to be laser-processed through the power setting means 526. Alternatively, the control means 524 may adjust the power of the laser beam LB to an appropriate value.

When an error is transmitted, for example, when the material of the wafer 4 is silicon and the surface 4a of the wafer 4 is coated with a metal film of aluminum or copper, the operator selects silicon by the power setting means 526. When I did. Then, when the laser beam LB irradiates the metal film on the surface 4a of the wafer 4, the type of material (aluminum or copper) specified by the control means 524 based on the plasma light P detected by the plasma light detection means 518, and Since the type of material (silicon) selected by the power setting means 526 is different, an error is transmitted.

After forming the cutting groove 256 in the wafer 4, the X-axis movable member 260 and the Z-axis movable member 262 of the holding means 502 are moved, and the lower surface of the frame 64 of the frame unit U held by the first elevating table 420 is temporarily placed. By contacting the upper surface of the frame support portion 228 of the table 204, the frame 64 is held by the magnetic force of the strong permanent magnet 402 positioned in the ascending position. At this time, in order to prevent debris adhering to the outer periphery of the wafer 4 from adhering to the suction hole 229, no suction force is generated in the suction hole 229 of the annular support portion 226, and the annular support portion 226 is positioned in the descending position. It is preferable to leave it.

Next, after releasing the suction force of the suction chuck 430 of the first elevating table 420, the first elevating table 420 is raised. As described above, since the magnetic force of the permanent magnet 424 of the first elevating table 420 is weaker than the magnetic force of the strong permanent magnet 402 of the temporary placement table 204, the frame 64 is passed from the permanent magnet 424 to the strong permanent magnet 402. Then, when the first elevating table 420 is raised, the frame unit U is held by the temporary placement table 204 and is separated from the first elevating table 420. In this way, the frame unit U is handed over from the first elevating table 420 to the temporary storage table 204.

Next, the temporary placement table 204 that has received the frame unit U is positioned below the separation portion 248 of the reinforcing portion removing means 194 by the temporary placement table transport portion 232 (see FIG. 10). At this time, the belt conveyor 300 of the disposal unit 276 is positioned at the standby position. Next, the second elevating table 272 of the separating portion 248 is lowered, and the lower surface of the second elevating table 272 is brought into contact with the tape 96 of the back surface 4b portion of the wafer 4. Next, a suction force is generated on the lower surface of the second elevating table 272, and the back surface 4b side of the wafer 4 of the frame unit U is sucked and held by the second elevating table 272.

Next, after the strong permanent magnet 402 of the temporary placement table 204 is positioned in the descending position, the second elevating table 272 that attracts and holds the wafer 4 of the frame unit U is raised. Next, after moving the temporary placement table 204 below the first elevating table 420, as shown in FIG. 17, the pair of feeding means 290 and the Z-axis feeding means 294 of the separator 274 are operated to operate the upper and lower sandwiching rollers. The frame 64 is sandwiched between the 292a and 292b in the vertical direction. Further, the belt conveyor 300 of the disposal unit 276 is positioned from the standby position to the collection position.

Next, while irradiating ultraviolet rays from the pair of ultraviolet irradiation portions 270 to reduce the adhesive force of the tape 96 attached to the ring-shaped reinforcing portion 24, the ring-shaped reinforcing portion 24 is pressed downward by the pressing roller 298. , The frame unit U is rotated by the motor 284 together with the support shaft 286 and the second elevating table 272 with respect to the separator 274. As a result, the ring-shaped reinforcing portion 24 can be separated from the frame unit U. The reinforcing portion 24 dropped from the frame unit U is conveyed to the dust box 302 by the belt conveyor 300 and collected. When separating the reinforcing portion 24, the separator 274 may be rotated with respect to the frame unit U.

After carrying out the reinforcing portion removing step, the ringless unit carrying-out step of carrying out the ring-less unit U'from which the ring-shaped reinforcing portion 24 has been removed from the reinforcing portion removing means 194 is carried out.

In the ringless unit carry-out process, first, the belt conveyor 300 of the disposal section 276 of the reinforcement section removing means 194 is positioned from the collection position to the standby position. Next, the frame holding portion 306 of the reversing mechanism 308 (see FIG. 19) of the ringless unit unloading means 196 is positioned below the ringless unit U'sucked and held by the second elevating table 272.

Next, the arm 318 is raised with the suction pad 326 of the frame holding portion 306 facing upward, and the ringless unit U'supported by the second elevating table 272 and the surface 4a of the wafer 4 faces downward. The suction pad 326 of the frame holding portion 306 is brought into contact with the lower surface side of the frame 64.

Next, a suction force is generated in the suction pad 326 of the frame holding portion 306, and the frame 64 of the ringless unit U'is sucked and held by the suction pad 326. Next, the suction holding of the ringless unit U'by the second elevating table 272 is released. As a result, the ringless unit U'is delivered from the second elevating table 272 of the reinforcing portion removing means 194 to the frame holding portion 306 of the ringless unit carrying out means 196.

After carrying out the ring-less unit unloading step, the ring-less unit accommodating step for accommodating the ring-less unit U'carried out by the ring-less unit unloading means 196 is carried out.

In the ringless unit accommodating step, first, the reversing mechanism 308 of the ringless unit carrying-out means 196 is turned upside down, and the ringless unit U'suctioned and held by the frame holding portion 306 is turned upside down. As a result, the ringless unit U'is located below the frame holding portion 306, and the surface 4a of the wafer 4 faces upward.

Next, the Y-axis movable member 316 and the arm 318 of the reversing mechanism 308 are moved so that the ringless unit U'is brought into contact with the upper surface of the pair of support plates 328 of the ringless unit support portion 310. At this time, the distance between the pair of support plates 328 is narrowed by the space adjusting means, and the pair of support plates 328 are in close contact with each other. Next, the suction holding of the ringless unit U'by the frame holding portion 306 is released, and the ringless unit U'is placed on the pair of support plates 328. Next, the heater mounted on each support plate 328 is operated to heat the tape 96 of the ringless unit U', thereby smoothing the deflection and wrinkles of the tape 96 caused by the removal of the reinforcing portion 24. Then, the ringless unit U'is sucked and held by the frame holding portion 306 again and raised.

Next, after widening the distance between the pair of support plates 328 by the spacing adjusting means, the ringless unit U'is placed on the upper surface of the support plates 328. Then, as shown in FIG. 21, the ringless unit U'supported by the ringless unit support portion 310 by the pressing piece 338 of the push-in portion 312 is pushed to enter the frame cassette 198 placed on the frame cassette table 200. Contain. As described above, in the processing unit 2, the dicing tape 96 is attached to the back surface 4b of the wafer 4 in which the ring-shaped reinforcing portion 24 is formed convexly on the back surface 4b corresponding to the outer peripheral surplus region 20, and the dicing tape 96 is attached to the frame 64. The work of integrating them is easy, and it is easy to cut the ring-shaped reinforcing portion 24 and remove it from the wafer 4, so that the productivity is improved.

As described above, in the laser processing apparatus 500 of the processing unit 2, the power of the laser beam LB to irradiate the wafer 4 is applied based on the detection result of the plasma light P emitted from the region processed by the irradiation of the laser beam LB. It can be easily adjusted.

4: Wafer 4a: Wafer front surface 4b: Wafer back surface 14: Device 16: Splitting line 18: Device area 20: Outer peripheral surplus area 23: Recessed portion 24: Reinforcing part 500: Laser processing device 502: Holding means 504: Laser beam irradiation Means 506: Moving means 510: Oscillator 512: Condenser 514: Branch path 516: Beam splitter 518: Plasma light detection means 526: Power setting means LB: Laser beam P: Plasma light

Claims (6)

A laser processing device that irradiates a wafer with a device area formed on the surface of a plurality of devices by a planned division line and a peripheral surplus area surrounding the device area with a laser beam to process the wafer.
The holding means for holding the wafer, the laser beam irradiating means for irradiating the boundary between the device region and the outer peripheral surplus region of the wafer held by the holding means, and the holding means and the laser beam irradiating means relatively. Equipped with a means of transportation to move
The laser beam irradiating means includes an oscillator that oscillates a laser beam, a condenser that collects the laser beam oscillated by the oscillator, and a plasma light detecting means that detects plasma light emitted from a region processed by irradiation of the laser beam. Laser processing equipment including. Further provided with a beam splitter disposed between the condenser and the oscillator to split plasma light emitted from a region processed by irradiation with a laser beam and lead to a branch path.
The laser processing apparatus according to claim 1, wherein the plasma light detecting means is arranged in the branch path. The laser processing apparatus according to claim 1, wherein the front surface or the back surface of the wafer is coated with a metal film, and a power setting means for selecting a material type and setting the power of a laser beam is provided. The laser processing apparatus according to claim 3, wherein an error is generated when the type of the material specified based on the plasma light detected by the plasma light detecting means and the type of the material selected by the power setting means are different. A recess is formed on the back surface corresponding to the device region of the wafer, a ring-shaped reinforcing portion is formed convexly on the back surface corresponding to the outer peripheral surplus region of the wafer, and the laser beam is applied to the base of the ring-shaped reinforcing portion. The laser processing apparatus according to claim 1, which is irradiated. The laser processing apparatus according to claim 1, wherein the irradiation of the laser beam is stopped when the plasma light detecting means stops detecting the plasma light.

Images